Automatic stop mechanism for sewing machines



7 1 J. BOSTON AUTOMATIC STOP MECHANISM FOR SEWING [MACHINES Oriiainal Filed Sept. 4. 1918 4 Sheets-Sheet 1.

May 17 1927. 1,629,090

J. B OSTQN Ap'romne STOP MECHANISM FOR SEWING MACHINES Original Filed Sept. 4, 1918 4 SheetsSheet 2 JED/7n Boaibm 1,629,090 J. BOSTON AUTOIIATIC STOP MECHANISM FOR SEWING HACEINES.

Originalfiled se i. 4.. 191g 4 sheets-shut s g fl ' 1 70/104 BOGtQ a 1,629,090 May 17 1927' J. BOSTON AUTOMATIC STOP MECHANISM FOR SEWING MACHINES Original Filed Sept. 4, 1918 4 Sheets-Shoot 4 Jbhn 13052 0, I

Patented May 17 1927 a- UNITED STATES PATENT OFFICE,

JOHN BOSTON, OI NEWARK, NEW JERSEY, ASSIGN'OR, BY MESNE ASSIGNMENTS, TO

- T. HARDEN CARTER.

AUTOMATIC STOP MECHANISM FOR SEWING MACHINES.

Original application filed September 4, 1918, Serial No. 252,527. Patent No. 1,502,544, dated July 22, 1924. Divided and this application filed September'18, 1923. Serial No. 663,489.

to a stop mechanism specially applicable to automatic hemstitching machines and the like such as are used for hemstitching the side edges of long strips of fabric which are subsequently cut into short lengths and hemstitched across the ends to form hand I will hereinafter describe my kerchiefs. invention as applied. to such machines, but without intending to limit it to such application. I

The present invention constitutes a division of application, Ser. No. 252,527, upon which Letters Patent No. 1,502,544, issued to me on July 22, 1924. I

One of the objects of my invention is to provide an improved mechanism particularly applicable to automatic sewing machines of the above character which will contribute to their automatic operation whereby a single operator without special training may attend a plurality of machines.

A further object is to provide reliable and eiiicient means adapted to be applied to sewing machines of the above character for automatically controlling the starting and stopping of the machine. The device, which is of simple and practical construction, is adapted to be positioned within easy reach of the operator from all positions around the machine, and in the preferred embodiment of the invention the automatic stopping device hereinafter described is associated or combined with a main operating lever in order that the latter will set the automatic device in condition for automatic operation. 7

A further object is to provide an automatic mechanism of the above character adapted to stop the machine on exhaustion of the supply of fabric whereby the machinewill cease its stitch'operation. This device in no way interferes with the operation of the stitching mechanism and is so constructwith the sewing machine proper.

Another object ofmy invention is to provide a mechanism for carrying out the above a which may be attached to the standard sewing machines now on the market without machine; and

rows if desired, whereby material modification thereof and without interfering with their operation and which mechanism shall be simple to manufacture and operate. I

Other objects will be in part obvious from the annexed drawings and in part indicated in connection therewith by the following analysis of the invention.

This invention accordingly consists in the features of construction, combination of parts and. in the unique relations of the members and. in the relative proportioning and dispositioning thereof, all as more clearly outlined herein.

To enable others skilled in the art so fully to comprehend the underlying features thereof that they may embody the same by numerous modifications in structure and relation contemplated by this invention, drawings depicting a preferred form have been annexed as a part of this disclosure,

and, in such drawings, like characters of reference denote corresponding parts throughout all the views, of which Figure 1 is a front elevation of a sewing machine with my improvement applied thereto, the gate being omitted;

Figure 2 is a partial rear elevational. view of the upper part of the machine;

Figure 3 is a partial plan view with the gate omitted;

Figure 4 is a side elevational view partly in section showing the lower part of the Figure 5 is a sectional view taken near the right hand end of the head of the machine.

Referring now to the drawings in detail and more particularly to Figure 1, there is illustrated a sewing machine head 1, of any desired type preferably suitable for hemstitching. This head is mounted upon an elongated bench 2 adapted'to support a plurality of similar machines in a row or they all may be driven from a single main source of power. The frame 3 of the machine is provided wlth a needle shaft 4 carrying a needle 5, a tensiondevice 6 and a take-up arm 7, a needle oscillatorlink 8, a balance wheel 9, a drlve pulley 10 and a spool holder 11, all of the 'of' speed.

on the counter shaft 28- thence 'to'a pulley- 25 on a short shaft 26 by means of which the sha'ft26 is'op'era'te'd from the counterusual well-known type and cooperating one with another as 1s familiar to those skilled in the art. The needle thread 12 leads from the spool through to a guide 123) and tension device 6 thence over apin 1 L- andarni 15 carried by a part of the take-up thence to the ne le The sew'ving inacliineprop'eris be operated from the main shaft 16by means of a belt 17, traveling over a pulley 18 to the pulley 101511 tho sewing machine. A worm 19 on the ,1nai11 shaft"-'6 operates through a worm 20; toturn ,a shaft-2} which latter operates through bevel gears 22 to rotate a couhtershaft at'a 'reduce' l"rate A; belt 24 passes over =ajpulley shaft 23 as will appear-inure clear byzreference to Figure 4.

The strip of fabiic to be stitched'is fed into the. machine 'over what is kno-wn as a gate'27i'as shown more cfearly in Figure 4 and fully' illustrate'dand described in my prior patent, No.: 1,391,8 7 6. and this gate forms nopart of the presentinvention specifically except in so far as' it entei's' into i certain combinationshereihafter set forth and claimed in connection-with my automatic stop DIQChHDISIII.

rear of the bench pver a roller-35 against" which it is lightly pressed 'bvicllefs 36 mounted on a vertically n'rovableshaft fi'i' ,journaled in brackets 38.

I lVhen desired the forward end of thefabric strip is directedffro'm the rollen35"'onto the ;tal eup-or reeling' rollei" 39 below the table, which roller is operatedfrom the short shaft 26 by'in'e ans of a cranlcpi'n 4O projectinginto one end of the -rol le1"and which serves to turn the roller inorder to wind the fabrreupo'n it. This, however. is fully'explained in the, parent application.

gerial No. 252527gmd need not berepeated.

It will be noted that the pulley. is provided with a second groove42 andfa belt 4.3 OIIQQQ'IHQ- tlusgroove operates a pulley H to drive the roller over whichthe fabric 1 .s has previously passed. The belt 24 which operates to turn-the shaft 26, when enjsraging the pulley25f, is adaptedito be shifted to the loose pulley 41 whenever the shaft. 261s to be thrown out of operatio-n, and

this is done through a shifting lever 415 pivoted at 46 and'operated through alink he fabric strip first passes over a rod'28 4:7 which link is fulcrulned above to one arm of a bell crank lever 48 rocking upon pin 49, Figure 5.

T0- the other arnr-of-th-isbell: crank lever 'there is fulcruined link. 50 having its other end pivoted to an arm 51 fixedon a short shaft journaled in a bracket 53 at the" rearof the machine frame;

A. second arm 54 fixed to this shaft has a connecting link- 55-pivoted to a starting levei 56, which in turn is pivoted at 57 in frontof the machine and provided with an operating -handle 58 atits upper end. This control lever 56 is adapted to set the entire mechanisni' incondition "for '"oporation as well :as to start the machine asxwill hereinafter be mote fully explained.

When th'e'lever is pulled' forward the shaft 52 is rocked so thatth e ai -m 5i op-'- crates through the'link '50 to rocli t-he bell crank 'leven 48 -This,;in tiirn pullsup on th'e 'link-47' torock the bell'era'nh lever 45 andshiftthe-belt24L froiir the loose' puiley ll tothe clutch pulley 25 'Wl1iCl1, lI1 am operates the roller 39; I

If the setting lever is released by the autonfatic stop 'mech anisin so that it moves back to'thepos'itionshown in FiQured, the opis shifted to the loose pulley 41 thus-throwing the-roller 39 out'of'operationo The lever 56, "above referred to; *operates also to throw the usual clutch 59' of the sewing; machine into and out of operationbymeansof abarn-lever 60' rocking onfnlicrum 61, causing a cam 62 to press in the ordinary clutch 59, Figure-l, whereby-the"pulley'10 willoperate'the sewing machines The other or-at'ions'are reversed, that -is,"th e belt-"24 211- 1163 of this camlevenis provided'wi'th a pin 64 on whieh-a spring'65 acts to rockthe cam lever 60 and thus releasethe-clutc'hof the machine The phi-"64 is "engaged by, an "aria-66 fixed to the shaft -52,-*which"latter,

as above stated, is-iocked by, the setting" lever :36.- lVhen' the shaft '52- is rocked by theforward"movement of'the setting lever 56. the arin -66 acts on the-pi'n '64", thereby to move the 'cam lever 60 and throw in the Y clutch-59. lVhene'ver the setting Zever 56 is rel.eased,-'-it is thrown back bythe aetionof -t-he sprinpg-"fifi which also ope-rates thecam lever 60.

Referring now more specifically to: the dethe tin-1e the end'of the-fabric has reached the needle attention is particularly directed to Figure 4. A spring fi'i is,adapted to be coiled aroundthe rod 31-of the 'gate and is provided with a springarm 68'restingon vice for stOppin -the machineat-or'about rweightds so poised; that the light pressure of-rthe arm 69 Will holditjust to oneside of the fulcrum 72 of the arm 71. hen the fabric ceases to hold up the spring arm 68v from near the vertical towards a horizontal position. A link 78 connects at one end to the arm 75 and at the other end to a bell crank lever 79. To the other arm of this bell crank lever a link 80 is attached with its upper end connected to one arm of a lever 81 pivoted at 82. The other arm of the lever 81 is provided with a cam-shaped member 83, Figures 2 and 3, adapted to act on a roller 84 carried by the lever 85. When the arm 75 is rocked by the swinging weight 70 to the dotted line position shown in Figure 4, as it will when the fabric ceases to support the arm 68, the action is transmitted through link 80 to lever 81, Figure 5, which acts on the roller 84 and to a slide 8O (specifically constructed and operable like the slide 80 in my copending application, Serial No. 663,490, filed September 18, 1923) to rock the lever 85 on its pivot 85*, and thus release a latch 86 so that the setting lever 56 moves back and stops the machine through clutch 59 and belt shifter 45 associated with the winding roll 39.

The operator may stop the machine at any time, of course, by release of latch 86 permitting the setting lever 56 to swing over, otherwise the machine operates automatically until the end of the fabric approaches the machine, whereupon the latch 86 is released, and the machine will be stopped and with it the reeling device 39.

It will thus be seen that the present invention provides a simple and practical device particularly applicable to automatic sewing machines adapted to stop the same if the supply of material to be stitched should become exhausted.

Without further analysis, theforegoing will so fully reveal the gist of the invention that others can, by applying current knowledge, readily adapt it for various applications without omitting certain features that,

from the standpointof the prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention, and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalency of the following claims.

I claim:

1. In a machine of the class described, a movable element, means to control operation of the machine through movement of said element, means to operate said element by feed of thematerial up to the point of exhaustion including a material-engaging device having a spring, a weighted lever arm normally held slightly to one side of its fulcrum by light pressure of said spring, and a connection flexible longitudinally disposed between said arm and element to enable the weight of the arm to exert maximum force on said element when released by said spring to draw said connection and thereby move the element and associated parts. i

2. In a machine of the class described, a rockable element, means to control operation of the machine through movement of said element, a spring urging said element to normally inactive position, means to operate said elemenfi by feed of the material up to the point of exhaustion including a material-engaging device having a spring, a weighted arm normally held slightly to one side of its fulcrum by light pressure of the spring, and a connection longitudinally flexible located between said arm and element to enable the weight of the arm to exert maximum force on said element when released by said first mentioned spring to draw said connection and thereby move the element and the associated parts.

3. In a machine of the class described, in combination, with a power-control clutch and a setting lever, a second lever, said second lever controlling said clutch, a spring urging said second lever to clutch releasing position, a connection between said setting lever and second lever whereby said spring also urges said setting lever to off position, latch means to hold said setting lever in set position, and means to automatically retract said latch means by feed of the material up to the point of exhaustion.

Witness my hand this 15th day 1923.

JOHN BOSTON.

of Sept, J 

